Research And Improvement Of Clustering Algorithms In Wireless Sensor Networks Based On LEACH

Wireless sensor networks (WSN) is applied to monitoring, sensing, collecting and processing the information from the monitored objects in real time. WSN has a wide range of applications such as military communication, environment monitoring and industrial production. Traditional wireless routing protocols are not suitable to WSN because the WSN usually has a high nodes density and the energy, computation capacity and bandwidth of nodes are usually restricted. Designing a routing protocol to save energy and prolong the lifetime of network effectively is one of the key points for the research of WSN. The main work of this thesis can be listed as follows:Firstly, several commonly used routing protocols are evaluated from different measurable indicators, then the disadvantages and advantages of LEACH (Low Energy adaptive Clustering Hierarchy) which is the widely used cluster-based routing protocol are analyzed.Secondly, because the cluster heads change frequently and energy efficiency is low in LEACH protocol, a modified protocol, LEACH-EAC (LEACH-based Energy Aware clustering method), is proposed to prolong the network's life cycle. The relationship between the network's lifecycle and node's energy is established, the upper bound and the lower bound of the cluster's lifetime is derived and a less cluster head rotation algorithm is proposed. Numerical simulation shows that LEACH-EAC is superior to LEACH on stability and network's lifecycle.Finally, the research is summed up and prospects are made in this thesis.